This invention relates to the field of skin treatment, more specifically to the use of light to change the appearance of the skin.
As light energy is absorbed within the skin, light can be used to achieve desired clinical results. In particular, light has been used to remove hair, eliminate leg veins, remove or reduce the color of tattoos. In addition, water absorption of light energy transforming light into heat energy has been used for laser ablation of the skin surface or for use of lasers as cutting instruments. Plastic surgeons, dermatologists and their patients continually search for new and improved methods to alter the appearance of the skin.
Presently, all of the methods using either lasers or intense pulsed light in treating the skin require that the emitted energy to be absorbed selectively within the skin. The object that absorbs that energy, is termed a chromophore. The chromophore can be a true color such as black or brown, or red. Alternatively, this is a molecule absorbing energy, such as water or protein complex. Selective chromophore absorption is the absorption of a particular type of light energy by a chromophore. A clinical treatment can work because of selective chromophore absorption, wherein light energy is selectively absorbed by a particular component of the skin. If light energy were non-selectively absorbed throughout the skin, damage and injury would occur. The current problem in present laser and intense light treatment of the skin is that the clinical gain is often limited because the amount of beneficial skin selective chromophore absorption is always limited by the amount of non-selective unwanted absorption of energy throughout the skin.
The foregoing and other objects, features, and advantages of the invention will become more apparent from the following detailed description of a several embodiments which proceeds with reference to the accompanying figures.
A method of altering the appearance of a region of skin is disclosed. The method includes applying an effective amount of sensitizing wavelength of light to the region, and applying an effective amount of a treatment wavelength of light to the region, wherein the treatment wavelength is a shorter wavelength than the sensitizing wavelength. The application of the effective amount of the sensitizing wavelength of light and the effective amount of the treatment wavelength of light results in a change in a physical property of the skin.
In one embodiment, a method of beneficially altering the appearance of a region of skin is disclosed. The method includes applying sequenced complementary pulses of light energy, emitted from a laser or intense pulsed light source, to chromophore targets in the skin. There is a synergistic amplification of clinical response that results in a change in a physical property of the skin.